Bujumbura: Security forces in Burundi said Monday they had arrested around 170 suspected rebels and seized a number of weapons in a crackdown ahead of next week`s presidential elections.

The Burundian army spokesman, Colonel Gaspard Baratuza, said the rebels were detained after clashes in the northern provinces of Kayanza and Cibitoke.

Police and local officials said 30 assault rifles and ammunition were seized in the northeastern province of Muyinga.

Provincial governor Aline Maniratunga said around 30 supporters of opposition leader Agathon Rwasa were arrested in the operation.

A former rebel leader, Rwasa is now the main opponent of Burundian President Pierre Nkurunziza, whose bid to stand for a third consecutive five-year term despite a constitutional two-term limit has sparked months of civil unrest and an attempted coup in mid-May.

Burundian troops fought with rebel soldiers near the border with Rwanda over the weekend, and paraded around 80 of them in front of the media.

Burundian rebel general Leonard Ngendakumana -- who took part in the failed coup in May to topple Nkurunziza -- has confirmed that soldiers loyal to the coup plot were involved in the fighting.

"Our troops are preparing attacks to stop Nkurunziza," he told AFP by telephone on Monday, dismissing the parading of the detainees as "propaganda".

Opposition groups say Nkurunziza`s re-election bid is unconstitutional and a violation of a peace deal that ended a dozen years of civil war in 2006.

There are fears the current crisis could plunge the impoverished, landlocked country back into civil war.

Parliamentary polls, in which Nkurunziza`s ruling CNDD-FDD scored a widely-expected landslide win, were held on May 29 but boycotted by the opposition and internationally condemned.

Burundi`s presidency meanwhile said Ugandan President Yoweri Museveni would also arrive in Bujumbura on Tuesday as part of regional efforts to mediate an end to the crisis.

The five-nation East African Community (EAC) last week called for elections to be delayed by two weeks, to July 30, to allow time for more talks between Nkurunziza`s ruling CNDD-FDD party and opposition groups -- although these talks have so far made no progress.

With the presidential elections now scheduled for July 21, a delay of less than a week, Museveni has been left with only several days to try to kickstart the talks.

Opposition and rights groups argue that weeks of protests and a violent crackdown by security forces mean free and fair elections are impossible.

The country has also been left without most of its independent media outlets, after several radio stations were attacked and destroyed in fighting during the attempted coup.

Over 70 people have been killed in more than two months of protests, with over 158,000 refugees fleeing to neighbouring countries, according to the latest UN figures.